Thanks Terry,
I am kind of glad I didn't get the email as it gave me an opportunity to look at the scene and convey how I would light it which was not far off from your set up.
Don't worry about not remembering flash settings, in all honesty they would make no difference to any input I would make, in my reply I was intentionally vague about shutter speed and f/stop because these are things that can only be determined when you are in the space on the day, It is pretty obvious you have a good command of your camera and a solid technical background so you will work it out. What I hope did come across clearly was the need to get more ambient into the frame and take some more control of your software.
I don't use any modifiers on site that often, just bare flash bounced into ceilings and walls, I do carry a couple of $1 shop white shower curtains though that I will bounce light off if the walls are going to induce a colour cast, I also use them to soften reflections of windows that are behind the camera. If I was shooting high end Architectural stuff I would bring a truck load of modifiers to the party.
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